LEAVES

Pecans are deciduous trees, shedding leaves in winter with new buds appearing in spring. Leaves are vital to growth and fruiting of all plants because of their important function in photosynthesis. They are particularly important for Pecans because of the heavy demands for food required in the maturing of the nuts. It has been calculated that 6 to 10 full leaves (90-150 leaflets) are required to mature a single Pecan nut. Leaves also provide the Pecan with plant food reserves for future years.

FLOWERS

Pecans flower during late spring. Pollen-bearing staminate and nut-producing pistillate flowers are developed separately and apart on the same tree. Frosts during flowering severely affect nut yields. Pollen is transferred by gravity and wind. Pecan pollen is known to blow freely over half a mile and under favourable conditions much farther.

NUT DEVELOPMENT

Pecan nuts develop slowly during the summer period inside a large outer green pod. The remarkably nutritious, unsaturated kernel gradually fills the already formed shell in 2 halves, or cotyledons. The shell hardens in late summer and autumn as the 'shuck' dries and breaks open.

ROOT SYSTEMS

Taproot - A one year old Pecan seedling can have a taproot up to 1.3 metres long whilst the aerial or above ground portion may be only 0.3 metres high.

In river valleys where soil is alluvial, deep, loose and fertile, Pecan taproots grow unimpaired until reaching a water saturated zone. Sometimes this can be 6 metres or more below the surface.

Lateral Roots - These roots grow horizontally and are the principal means of feeding the tree. Branching outward, they occupy an area much greater than that covered by the limb spread.

STEMS

When commercially grown, the young central stem is pruned to ensure that it grows singularly and vertically - this becomes the trunk. Limbs are pruned to ensure they are well spaced on the trunk to regulate sunlight and influence photosynthesis by allowing sunlight to penetrate the interior. Lateral branch growth is stimulated from the limbs: these are potential fruiting branches.

NUT PRODUCTION

Pecan trees take up to ten years to bear nuts and do not reach maximum production until the age of twelve to fifteen years. Like many fruiting trees they are 'alternate-baring' with 'on year' crops yielding up to 40% more than 'off years'. Commercially farmed trees will each produce up to 60kg of nut-in-shell in an 'on year', which will in turn yield about 35kg of Pecan kernel.